Stringed musical instrument



May 27, 1930.

J. SPERDUTl STRINGED MUSICAL INSTRUMENT Filed Aug. 16 1.928 2 SheetsSheet l d r e By ATTORNEU May 27, 1930. .1. SPERDUTI I v1,760,789

STRINGED MUSICAL INSTRUMENT Filed Aug. 16. 1928" 2 Sheets-Sheet 2 1 N VEN TOR.

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BY ATTORNEYJJ Patented May 27, 1930 UNKTED STATES P JOHN SFERDUTI, OF PLEASANTVILLE, NEW YQRK STRING-ED MUSICAL INSTRUMENT Application filed. August 16, 1928.

This invention has relation to musical instruments of the guitar and; banjo type, in which the strings are stretched over a sound vibrating body and along the neck, the latter terminating ina head carrying the stretch ing and tuning keys. A distinguishing teature between the guitar and banjo is that the guitar is formed with an elongated wooden body and is provided with a closed 19 back, and a substantially closed top, the latter however having a pair of sound holes or slots; whereas the banjo is constructed with a cylindrical body, covered on top with a vibratory stretched skin, and usually open at the back.

By reason of the differences in structure and material between the two instruments there is a remarkable diii'erence in tonal quality and reverberatory eiiects well known to and appreciated by musicians and listeners.

The object of the present invention is to produce an instrument which will combine the tonal qualities of both instruments and partake of the advantage of both. The invention accordingly consists in the novel con struction of such an instrument in accordance with the specific description hereafter given.

In the accompanying drawings constituting a part of this specification.

Figure 1 is a top plan view of an instrument embodying my invention;

Figure 2 is a side view of the same;

Figure 3 is a bottom plan view;

Figure 4 is a vertical central sectional view of the body of the instrument on a larger scale, taken in the longitudinal direction, on the dotted line l-ft of Figure 1;

Figure 5 is a similar view on the dotted line 0 55 of Figure 1; and t Figure 6 is a sectional view of a part of the bottom of the body of the instrument.

The instrument as illustrated is of the general characteristic form or model or a banjo and comprises a body, comprising the circular wall 2 secured at its lower edge to a lower border rim or flange 3, which extends outward. The wall 2 and border rim 3 are made of wood of suitable character and.

quality, as is also the flat bottom or back 4h braces the outside of the body wall 2, below QFFIQE The numeral 5 designates the head or top of the instrument, which consists of a skin or membrane which, at its edge is stretched over a hoop 6. This ring fits over and emthe upper edge of the latter, so theskin or membrane will rest upon said edge. The, skin and hoop are held in position. by means of a flattened ring 7 which is secured to rim or flange 3 by means of the posts or bolts 8, which pass through holes bored at intervals through the ring 7 and rim 3; These posts or bolts are provided with the usual screw heads 9 having kerfs or notches; for the application of an ordinary screw driver, and are adjustably held in place by nuts 10 on their lower ends below the rim 3. The back 4 of the drum is a circular flat section of Wood, such as mahogany or other suitable wood and is in the form of a wide surfaced ring, which provides an opening 12 in the center. The size of this, opening'may vary according to suitable tone requirements v and is intended to provide a substantially open back, as'in banjos or like instruments in which the characteristic banjo tone is to a great extent dependent on unobstructed vibrationsjof air below thev skin or head membrane. The provision, however, of a partially closed back, as in the present in stance has the efifect of imparting to the vibrations certain qualities, which are abient} from a banjo. having an entirely open ack. i

plj'ovide howev r for e se ta c ose back, where it is desirable to mod fy the tonal, effects, and for this purpose employ a closure consisting of a circular plate 1 3 of wood of suitablequality fittingthe central opening 12 and. having a ledge 1 4, which abuts against the lower surface of the back 4, and. is secured in position bylocking members 16, which are movable radial slots 17 in the closure 13 and which may be tightened up by the use or a screwdriver. V

By the provision of this closure it will be seen that the instrument can be readily changed from one having banj "s to one somewhat simulat o characten jg those a The purpose of the ring 7 and the bolts 8 is obviously to tighten up the membranous head or skin. This ring is made of metal and preferably of aluminum.

The neck of the instrument is designated, generally by the numeral 20, and is of the usual form. At its inner end the neck is formed with shoulder or shoe 21, which is channeled or mortised at 22 to embrace the ring 7. The rim 3 is formed with a notch or channel 23 for the passage of the shoe 21, so that the latter may be moved independently of the body of the instrument in tightening up the skin by the adjustment of the bolts, which adjustment draws down the ring 7 and thereby exerts pressure on the ring 6 suiiicient to stretch and tighten the mem braneous head. To adjust the ring 7, the screw 36 attaching the neck of the drum is removed.

Inasmuch as sound holes or openings are necessary in guitars, which have closed backs, but cannot be made in skin heads, I provide the back of the present instrument with holes 30, arranged at intervals in a circle to allow the escape of the sound vibrations, and these are suitably lined with eyelets to give finish and durability to the same.

The neck 20 is of the usual guitar con struction and is provided at suitable intervals with frets 31 of which the drawing shows eighteen.

The strings 32 are stretched from the rear portion of the body to the key section or head 32, which is formed with two similar longi tudinal slots 33, for the passage of the strings, in two groups of three strings each to the tuning keys 3a. A bridge 35 rests on the membraneous head and is of the usual notched character and preferably constructed of bone or ivory. The strings, at their rear ends, are looped and attached to hooks 36 upset from a plate 37 which is attached by screws to the block 38, mounted be tween the ring 7 and the rim 3. A cover or cap 39 is hinged to the lower edge of the plate 37 and may be raised and lowered to cover and uncover the string fastening devices. A slot 40 is formed in the depending section of the cap for the passage of a screw 4-2 secured to the block 38 and having a flattened head of greater width in one direction than the slot 40 so that when the cap is raised and the screw head passed through the slot, the screw may be twined so as to lock the cap in place.

l Vhat I claim as new is 1. A stringed musical instrument of the banjo type comprising a cylindrical body having a membranous head, and means for tensioning said head, said body being provided with a closed back in the form of a flattened ring and a central, detachable, closure disk, said ring being provided with spaced apertures.

2. A stringed musical instrument of the character described having a membranous head and a closed back, and having spaced sound apertures therein, said back comprising a fiat ring, the aperture of which is closed by a detachable closing cap.

3. A musical instrument of the banjo type, comprising a cylindrical body having a wooden ring shaped back provided with sound openings, a detachable central closure, a membranous head, a hoop over which said head is stretched, a ring which encircles the body and rests on said hoop, and means connecting said ring and body whereby the ring may be adjusted to tension said head.

t. A musical instrument of the banjo type comprising a cylindrical body having a ledge at its lower portion, a ring shaped bottom attached to said ledge and having a detachable central cap, a membranous head, a hoop over which said. head is stretched, a metallic ring embracin said body and resting on said hoop, bolts connecting said ring and said ledge and adjustable to move said ring and tension said head.

In testimony whereof I aiiix my signature.

JOHN SPERDUTI. 

